that spread Disease. 43 



South African biliary fever of horses. It is known to attack oxen, 

 sheep, horses and dogs, and has also been met with upon antelopes, 

 giraffes and elephants. 



Ixodes ricinus Linn, is apparently the chief carrier of redwater 

 fever, a form of piroplasmosis, in cattle in Northern Europe. It 

 ranges through Europe, North Africa, Transcaucasia, Arabia, 

 China, Japan and North America. It is met with upon sheep, 

 cattle, goats, horses, dogs, deer, hedgehogs, and many other 

 mammals, also lizards, and occasionally on man. 



Amblyomma hebraeum Koch is known as the bont tick ; it is a 

 common species in South Africa, and is distributed as far as 

 Central Africa. Owing to the fact that it transmits heartwater in 

 sheep, goats, and sometimes in cattle, this tick is of considerable 

 importance to agriculturists. Further remarks upon the bont tick 

 are given below. 



The third group includes examples of ticks that are not known 

 to convey disease to man or other vertebrates ; three species are 

 shown, as follows : — 



Amhh/omma cohacrens Donitz is found in Uganda upon 

 buffaloes. 



Dermacentor rhinocerotis de Geer ranges from South Africa to 

 Uganda and British East Africa, and is found usually upon the 

 rhinoceros, but sometimes on antelopes. 



Derinacentor circumguttatits Nn. is met with upon elephants in 

 Uganda and West Africa. 



In one of the table-cases in the middle of the Hoor of the Hall 

 is a series of specimens and enlarged models of the bont tick, 

 Amhhjomma hebraeum Koch, an African tick parasitic upon sheep, 

 goats and oxen. The exhibited series includes a drawing of a 

 small group of eggs, a model of a larva enlarged to the same size 

 as the models of the adult, namely 20 diameters, and another 

 model of the same larva still further enlarged ( x 120) to show the 

 details of structure. Models are shown of an adult male and 

 female ( x 20), and actual specimens are mounted on the tablet 

 between them. The great model in the middle of the case repre- 

 sents the female when fully gorged and distended with blood and 

 eggs, magnified to the same extent ( x 20). Two actual specimens 

 of gorged females, of the size of cherries, are shown in the small 

 glass vessel of alcohol. 



The bont tick is capable of transmitting to sheep, goats and 



